Protective device



H. G. FRENCH.

PROTECTIVE DEVICE.

APPLICATION FILED OCT. 24,1919.

Patented Nov. 15, 1921.

Inventor: Henry 6.135;; b M

5 His Attorney.

' and biased into driving engagement by a Schenectady,

HENRY G. rRENoH,

0F SCHENECTADY, NE YORK, ASSIGl-IGB 'IO GENERAL ELECTRIC COMPANY, A CORPORATION 0.? NEW YORK.

PROTECTIVE DEVICE.

Specification of Letters Patent.

Patented Nov. 15,1921.

Application filed October 24, 1919. Serial No. 333,626.

To all whom it may concern.

Be it known that I, HENRY G. FRENCH, a citizen of the United States, residing at county of Schenectady, State of New York, have invented certain new and useful Improvements in Protective Devices, of which the following is a specification. 7

My invention relates to protective devices, particularly to relays and has for its object to provide a relay of the induction type which will be positively set into operation upon the occurrence of any predetermined abnormal condition, which will positively and definitely move to complete its path of movement, which is quickly reset to its initial position and which consists of other improvements which will be set forth more in detail hereinafter.

The novel features which I believe to be characteristic of my invention will be definitely indicated in the claims appended hereto while the features of construction and mode of operation will be understood by reference to the following description taken in connection with the accompanying drawing in which:

Figure 1 shows, in perspective, a relay embodying the principle of my invention. and Fig. 2 shows in outline, the wiring diagram for my device.

My novel and improved relay comprises a rotatable armature 1, movable with atime delay by a permanent magnet 2 and controlled by a torque producing device com prising a motor element 3, and a counter torque or restraining element 4'. The restraining element 1 comprises, preferably a spring operatively related to a contact carrying shaft 5. This shaft carries a movable contact member 6 which is adapted to be moved into and out of engagement with cooperating fixed contacts 7 to close an auxiliary tripping circuit, as best shown in Fig. 2. The armature 1 is-carried by a shaft 8 which is movable into and out of driving relation with shaft 5 by means of a clutch device which is of the electromagnetic type. This clutch device consists of friction engaging disks or plates 9 carried by shafts 5 and 8 spring 10. The disks 9 ofthe clutch device are controlled by an electromagnetic element comprising a magnetic member 11- having pole pieces 12 on opposite sides of shaft 8 and in magnetic relation to the lower disk 9. The member 11 also carries two windings 18 and 14, one ad acent each pole piece 12.

.Vhen either coil is energized, the flux across pole pieces 12 acts upon the lower disk 9 attracting it as an armature against th action of spring 10 and thereby mowing it out of engagement with the upper disk 9. The clutch is then disengaged and the shaft 5 with contact 6 is then movable independent of the armature 1. The coils 13 and 14 of the clutch control device are operative in response to different conditions, one coil being energized when the contacts 6 and 7 are brought into engagement, while the other coil is energized in response to the falling off of the abnormal condition before the relay contacts engage, as will be described more in detail hereinafter.

The motor element 3 comprises a main winding 15 connectedthrough a transformer 16 to the circuit 17 to be protected and a compensating means including an auxiliary winding 18. The eifect of the auxiliary winding 18 is controlled by an electromagnetic device 19. This device comprises a magnetic circuit member 20 carrying winding 21, as best shown in Fig. 2, and provided with a variable air gap controlled by a movable plunger 22. The position of plunger 22 maybe variedand the air gap controlled by an adjusting means 23. As best shown in Fig. 2, the compensating or auxiliary winding 18 is in a normally closed series circuit with the winding 21 of electromagnetic device 19, the winding 18 being in inductive relation with the main winding 15 of the motor element 3. Normally clutch 9 is in engagement and the effect of the restraining or counter torque element overcomes the effect of the torque or motor element 3.

As the load increases in the circuit 1'? more current passes through winding 15 of the niotor'element 3 and more current is induced in the auxiliary winding 18 which causes a corresponding increases in current in winding 21'of electromagnetic device 19.

Upon the passage of a predetermined cur-' rent in circuit 17, the current flowing in winding21 is sufficient to pick up plunger 22 and close the air gap in the magnetic circuit member 20. The closure of this air gap increases the inductance of the winding 21 which acts to decrease the current in auxiliary winding 18 of the motor element. The

windings '15 and 18 of the. motor element 3 are so shifted in response to operation of electromagnetic device 19 that an increase of .torque is produced by the motor element 3 on the rotatable armature 1. This increase in driving torque is sufiicien't'to overcome the counter torque exerted by the restraining or counter torque element 4 and move the armature 1 in contact controlling direction. The'increase in counter torque producedby the spring 4 as the armature 1 is rotated, is compensated for, by the increase in torque produced bythe effect of auxiliary winding 18 so that the armature is carried positively into contact closing position bringing the contacts G and 7 into engagement. The c'losureof these contacts energizes the circuitof tripjcoil 24to open switch 25 controlling the circuit 17 to be protected.

The engagement of contacts 6 and 7 to energize trip coil 24, also energizes the coil 14 of the clutch control device, which in. series, as best shown in Fig. 2. This coll 14- through its magnetic member 11 attracts the lower d sk 9 of'the clutch and movesthe dlsk 9 out of engagement with its cooperating disk against the. action of spring 10. This disengagement of disks '9 moves the shafts 5 and 8 out of driving engagement and removes the effect of the restraining element or spring 8 upon the armature 1. The spring4thereupon exerts its effect to return shaft 5 and the movable contact 6 quickly to initial position against stop 26 independent of armature 1 thereby quickly resetting'the relay while the armature remains undisturbed. The stop. QG iscarriedon an adjustable arm 27 by means of whichithe position of the stop can bevaried to vary the path of movement of, contact 6 and h'encethe time element of the relay. The resetting of the contact 6 breaks the circuit of coil 14 and disks 9 of the clutch, and returns it in position for the next operation.

It often happens that the overload necessary to start the armature into' operation falls off before the relay has had time to operate, that is, before the'armature has completed its path of movement. Under such circumstances, it is essential to return the relay to its initial position quickly with: out theefiect of floating. To meet this condition, I have provided a control device operativeto energize the other coil 13 of the clutch control element to quickly reset the contacts as has been described. This device comprises a permanentrmagnet 28 betweenthe poles of which the armature 1 is rotatable. mounted upon a support 29' and carries a movable arm 30 having a contact member 31. Cooperating with themovable contact 31' is a fixed contact member 32 which con- The magnet 28 is pivotally.

tacts control the circuit of coil 13 as shown in Fig. 2. The magnet 28 and contact arm 30 are biased to bring contacts 31 and 32 into engagement by any suitable means such as spring 33. Also associated with the end of arm 30 is a double lever device controlled by the electromagnet 19. This'device consists of levers 34 and. 35 secured to opposite ends of a shaft 36 and movable as a unit. Lever 34 has a lug 37 extending into the path of movement of arm 30. and lever 35 has a lug 38 extending into the path of movement of plunger 22 of electromagnet 19. Normally plunger 22 of electromagnetic device 19 engages lug 38 of lever 35 and through lever 34, its lug'37' engages the end of arm 30 and holds the contacts 31 and 32 out of engagement. Then plunger 22 picks up and the armature 1 starts to rotate the restraint'of lever 34 is removed. The efi'ect of induction, however, moves the magnet 28 on its pivot in a direction such that the arm 30 still'holds contacts 31 and 32- out of en gagement during the movement of the arma 'ture 1 in contact closmg direction.

overload falls off, however, before the armature 1 has brought the-relay contactso and 7 into engagement, thereby causing the armature to be retarded in its movement,

the pull exerted by spring 33 moves the magnet 28 on its pivot and brings arm 30 nto a position where contacts 31'and 32 engage, as can best be seen in Fig. 2. The engagement of contacts 31 and 32 closes a circuit to ener ize clutch Winding 13 which thereupon acts to separate the disks 9 and, as before explained, permits the contacts 6 to be immediately reset independent of the.

armature.

If the What I claim as new and desire to secure a rotatable armature, fixed contacts, a cooperating contact movable by the rotation of said armature into-engagement'with said fixed contacts, a torque element'for rotating said armature, and a restraining element cooperating with said armature to oppose the action of said torque element, and means responsive to predetermined electrical conditions for causingsaid cooperating contact to be moved in contact engaging direction in response to said armature and in the pposite direction in response to said restrainmg element, independent of said armature.

3. In a relay device, the combination with fixed contacts, and a movable contact member, of a rotatable armature, a torque element for rotating said armature, and means for causing said armature to carry said movable contact into engagement with said fixed contacts and for returning said contact to its initial position independent of said armature.

4. A relay comprising relatively movable cooperating contacts, a rotatable armature member, a torque member for rotatingsaid armature, means normallyexerting a counter torque on said armature, means for discon necting said counter torque means from said armature in response to predetermined elec trical conditions, a fixed contact, and a movable contact carried into engagement with said fixed contact by the rotation of said armature, and returned to initial position by said counter torque means.

5. In a relay device, the combination with a rotatable armature, a torque element for rotating said armature in one direction, a counter torque element acting to restrain the rotation of said armature and adapted to be disconnected therefrom, means for disconnecting said counter torque element, fixed contacts, and a cooperating contact controlled by said counter torque element.

6. In a relay device, the combination with a rotatable armature, a torque element for rotating said armature, relatively movable cooperating contacts adapted to be brought into engagement by the rotation of said armature, and means for resetting said con tacts independent of said armature.

7 .In a relay device, the combination with a rotatable armature, a shaft therefor, a cooperating shaft, a movable contact carried by said cooperating shaft, a fixed contact with which said movable contact is engageable, a torque element for rotating said armature, means for causing a rotation of said cooperating shaft in response to rotation of said armature shaft to carry said movable contact into engagement with said fixed contact, and means for rotating said cooperating shaft in the opposite direction independent of said armature shaft to return said movable contact to its initial position.

8. In a relay device, the combination with a rotatable armature, a torque element operative in responseto current above a predetermined amount for rotating said armature, a fixed contact, a movable contact carried into engagement with said fixed contact in response to rotation of said armature, and means for quickly returning said movable contact to its initial position independent of said armature in response to the engagement of said contacts and at any point in the path of movement of said movable con tact if the current falls below said predetermined amount.

9. In a relay device, the combination with a rotatable armature, means restraining said armature against movement, contacts controlled by said armature, means for overcoming said restraining means and rotating said armature in contact controlling direction in response to abnormal conditions above a predetermined amount, and means operative-in response to the engagement of said contacts and in response to the falling of said abnormal conditions below said predetermined amount for quickly resetting said contacts in their initial position.

10. In a relay device, the combination with a fixed contact, a movable contact engageable therewith and biased to initial position, a rotatable armature, means for rotating said armature in response to current in excess of a predetermined amount, means normally operative to cause said movable contact to be moved in response to rotation of said armature in a direction to engage said fixed contact but operative in response to the engagement of said contacts and to the falling of the current below said predetermined amount to enable said movable contact to quickly return under its bias to initial position independent of said armature.

11. In a relay device, the combination with a rotatable armature, contacts controlled thereby, a torque element for moving said armature into contact controlling position, a counter torque element normally predominating but overcome by said torque element in response to abnormal conditions above a predetermined amount, means for compensating for the increase in effect of said coun ter torque element as said armature is ro- .tated in response to said torque element, and means for quickly effecting the resetting of said contacts to initial position independent of'said armature in response to the engagement of said engagement and the falling of conditions below said predetermined amount.

12. In a relay device, the combination with a rotatable armature, a fixed contact, an independently movable contact adapted to be moved thereby into engagement with said predetermined contact, a torque element for rotating said armature in contact engaging direction, biasing means for holding said movablecontact in initial position, and means for rendering said movable contact operative in response to rotation of said armature to move into engagement with said fixed contact, and means for rendering said first mentioned means inoperative in response to the engagement of said contacts.

13. In a relay device, the combination with a rotatable armature of a torque element tending to move said armature in one direction, a counter torque element exerting a restralnlng effect on said armature, a fixed'contact, and a cooperating contact movable into 7 engagement with said fixed contact in response to said torqueelement and to initial position independent of said armature in response to said counter torque element;

14;. In a relay device, the combination with relatively movablecooperating contacts, of actuating means for moving said contacts into engagement in response to abnormal conditions above a predeterminedamount,

and means for quickly returning said contacts from engaging to initial position andfrom any intermediate point in response to the falling of said abnormal conditions below said predetermined amount independent of said actuating means.

' "151111 a relay device,the combination with afrotatable armature,- a torque element vfor rotating sald armature 1n one direction, an

/ independent spring element adapted to be connected to said armature to oppose the action of said torque element, a movable contact carried by said spring element,ea 00 operating fixed contact, a clutch devlcepnormally acting to connect said spring element to said armature whereby said movable contact is carried into engaging position in response to the rotation of said armature under the increasing restraining force exerted by said spring, and means operative in're-V sponse to the engagement of said contacts for disengagingsaid clutch device whereby the tension exerted by said spring'returns said movable contact quickly to initial position independent ofsaid armature. 16. In a relay device, the combination with a movable contact, a cooperating. fixed contact, a spring acting to holdsaid movable contact in initial position, an actuating means, and means for connectlng saldmovable contact to saidactuating means to, cause its movement thereby. into engagement wlth said fixed contact against the' action exerted by said spring, and means responsive tojth e engagement of said contacts for disconnect-1 

